Do farmers with less education realize higher yield gains from GM maize in developing countries? Evidence from the Philippines

For genetically-modified (GM) maize with genes for insecticidal Bacillus thuringiensis (Bt) toxin expression and glyphosate tolerance, there is ample developing world evidence demonstrating general increases in farmer average yields. However, little work carefully examines farmer profiles to explain mechanisms for heterogeneity in yield effects. In this article, we view Bt and stacked traits as simplifying input components, removing much complexity in farmer pest control needs. With panel data from the Philippines, we test whether these traits serve as substitutes or complements to human capital. We thus examine an oft-discussed but previously unexplored facet of Bt technology impacts. Results indicate GM traits are substitutes with proxies for human capital and pest control knowledge. For every year decrease in formal education and maize farming experience, farmers realize significantly higher yield gains from planting GM maize. This evidence provides additional insights about ‘pro-poor’ claims of many GM proponents, given small-scale, poor farmers tend to have lower levels of education.